Hi Roger,
Yes I see that now. In that case, as long as the PTT (SEND) line can sink at least 10mA it can connect directly to the base of Q2. Then, remove D1, R2, R3 and Q1.
Thanks for the feedback.
Search found 37 matches
- Sun Nov 11, 2018 3:50 am
- Forum: SDR Antennas
- Topic: A FOOLPROOF ANTENNA SWITCH
- Replies: 30
- Views: 223380
- Sat Nov 10, 2018 11:04 pm
- Forum: SDR Antennas
- Topic: A FOOLPROOF ANTENNA SWITCH
- Replies: 30
- Views: 223380
Re: A FOOLPROOF ANTENNA SWITCH
Thank you to Glovisol for his excellent and elegant circuit. As he says in his text there is a way to protect the receiver in case of failure of the 12 volt supply to the circuit. I think my version of his circuit was his intention. RX Isolator.png Consider the modifications of his circuit as shown ...
- Sat Oct 13, 2018 9:23 pm
- Forum: SDRplay related
- Topic: RSP1A - RF Damaged?
- Replies: 5
- Views: 18151
Re: RSP1A - RF Damaged?
Hi John,
How do you know it is damaged?
What tests have you carried out?
Most things are repairable - for a price.
If it really is damaged your first stop is to seek advice from SDRplay support
How do you know it is damaged?
What tests have you carried out?
Most things are repairable - for a price.
If it really is damaged your first stop is to seek advice from SDRplay support
- Sun May 20, 2018 8:54 am
- Forum: SDRplay related
- Topic: HOW ABOUT A TRACKING GENERATOR?
- Replies: 3
- Views: 12575
Re: HOW ABOUT A TRACKING GENERATOR?
One of our group is working on a spectrum analyzer package for the SDRplay. He talks about the challenges of including a tracking generator.
viewtopic.php?f=12&t=3164
viewtopic.php?f=12&t=3164
- Wed Apr 11, 2018 6:43 am
- Forum: General
- Topic: Creating a 12 volt bias T for any RSP model
- Replies: 2
- Views: 11259
Re: Creating a 12 volt bias T for any RSP model
I don't understand your concept of reverse in this description. It sounds like you are simply planning to use the bias tee the correct way. The tee has a DC supply input. This DC is fed to the coax/socket that goes to the preamp/antenna system. The remaining coax/socket has a DC block (capacitor) an...
- Wed Jan 31, 2018 7:27 pm
- Forum: General
- Topic: Enough protection with antenna switch?
- Replies: 10
- Views: 32135
Re: Enough protection with antenna switch?
I think it's important that every user take heed of what radioham has found. Doing a measurement like this put him in control of protecting his own gear and gives him some understanding of his own systems performance. One thing he could do is add a second changeover relay in the RX leg that switches...
- Sun Dec 24, 2017 11:24 pm
- Forum: General
- Topic: RSP2 RF Protection Question
- Replies: 11
- Views: 39834
Re: RSP2 RF Protection Question
Thanks Support, It strikes me that 75W is quite a bit of power for satellite work but I don't know Jim's situation. I suggested low power TX because that will offer Jim nearly 19dB of extra protection during testing. Assuming no losses in the system(s) 1W = 30dBm add 50dB attenuation = -20dBm = a sa...
- Sun Dec 24, 2017 9:38 pm
- Forum: General
- Topic: RSP2 RF Protection Question
- Replies: 11
- Views: 39834
Re: RSP2 RF Protection Question
Hi Jim, I think you first need to assure yourself that your scenario won't blow out your RSP. In this situation +10dBm is a HUGE signal and if S9 = -93dBm then according to support S9 + 103dB is the absolute maximum signal level you should ever measure at the input to the RSP. If you don't have meas...
- Sun Nov 26, 2017 7:20 pm
- Forum: SDRplay related
- Topic: RSP2 USB failure?
- Replies: 7
- Views: 19709
Re: RSP2 USB failure?
Hi Phil,
Indeed a good result.
Indeed a good result.
- Sat Nov 25, 2017 12:22 pm
- Forum: SDRplay related
- Topic: RSP2 USB failure?
- Replies: 7
- Views: 19709
Re: RSP2 USB failure?
Hi Phil,
Can you share the solution with us?
Can you share the solution with us?